Toward a 5 TeV e e Collider - SLAC | Bold People ... · short-bunch wakefields superconducting...
Transcript of Toward a 5 TeV e e Collider - SLAC | Bold People ... · short-bunch wakefields superconducting...
Toward a 5 TeV e+e- Collider
Accelerator Research Department B,SLAC, Stanford University
http://beam.slac.stanford.edu
Our Charge
Invent, Design, Build & Commission
a 1 GeV/m x 1m linac,
with a technologyscalable to a 5TeV e+e- collider.
How to Invent an Accelerator?
Problem: 1 GeV/m =>
structure damage?
e-SOURCE
STRUCTURE
Gradients Today
10- 2
10- 1
100
101
102
10- 3 10- 2 10- 1 100 101 102
G
(GeV
/m)
λ(cm)
LWFA
PBWA
CLIC
NLCSLC
Breakdown
Trapping
120 °C80 °C40 °C
5 TeV Discussions at Snowmass
lasers & beamslaser wakefield accelerationγγ colliderklystrons & gyrotronsshort-bunch wakefieldssuperconducting linacs & technologyTHz radiationdielectric acceleratorsmm-wave accelerators & microfabrication, LIGA
Themes
Directions
SCRF Padamsee, Cornell30GHz Two-Beam - Westenskow, LBNL Tube Driven - Wilson & Irwin, SLAC90GHz Dielectric - Gai, ANL Conducting - Song, ANL, Whittum &
Siemann, SLAC1THz Chattopadhyay, Zolotorev - LBNLLaser Structure-Based, Huang, Stanford
Plasma-Based, [Esarey & Multitudes]Beam Structure-Based, Gai, ANL
Plasma-Based, UCLAγγ Kim, Xie, LBNL
Status of 5 TeV Concepts
SCRF
30GHz TBA30GHz Tube Driven
90GHz Dielectric90GHz Conducting
1THz
Laser Structure-BasedLaser Plasma-Based
Beam Structure-BasedBeam Plasma Based
γγ
100MV/m 60km SC materials research, site
200MV/m 30kmpower source prototype, drive beam dynamics, sitesheet beam klystron research, site
1GV/m <10kmpower source inventionpower source invention, structure invention
power source invention, structure invention
10GV/m ˜km module prototype, rep rating, stagingmodule prototype, rep rating, staging
module prototype, stagingmodule prototype, staging
[this or neutral beams a required adjunct to other concepts]
Scalings
high Υγγ
neutral beams
β∗ σz
I P
λGf repNbN
Linac FF
Vocabulary
Luminosity
Upsilon avg γ energy/beam e- energy
Beamstrahlung avg e- energyloss /beam e- energy
Lf N N
Rcmrep b
y= ≈ − −
2
235 2 1
410
πσsec
δ α σγB
z
er≈
+ ( )( )
= −1 241 1 5
0 01 12 2
2 3 2..
./
Υ
Υ
Υ =+( )
= −0 8331
0 3 10002
. .N r
Re
z y
γασ σ
Neutral Beams
●multiple bunch linac●beam combining●uncertain initial state●alignment, optics, N●instability limits D
e- & e+e- & e+
Hose Instability(Rosenzweig, et al.)
ξ1
ξ2
ξ3
ξ4
ee ++ ee ++
ee -- ee --
Beam Combining
IPFF
n
n-1
2
1
ρ−ρ
Lcδj=center energy offset of beamline j
Lw
●Lc is bounded below due to emittance growth from synchrotron radiation
●neutral beams are required
Structure Research(at different λ)
●Channel Guiding for LWFA(Multitudes)
●DDS Structure (Kroll, et al., NLC)
●Laser Linac(Huang & Byer, Stanford)
●mm-wave fabrication (Song, ANL )
Power Sources
●sheet beam klystron ●two-beam accelerator●gyroklsytrons●lasers
Wakefield Research
●planar structure wakefields
●short-bunch wakefields
●SLC collimator wakefield
●wakefield instrumentation
5 TeV ProblemsSmall Spot? ➜IP Limitations
New Structure? ➜Wakefields , Beam Dynamics
2cm>λ>10µm? ➜Power Source, Efficiency
G>100MeV/m?➜Efficiency
Ultra-Low Emittance?➜Source, Beam Dynamics
Parameters for λ=1cm 3mm 1mm LWFA, LS, PWFA...
ARDB People
StaffAngie SeymourAl Menegat
Prof’sBob SiemannDavid Whittum
Grad StudentsBoris PodobedovDavid Pritzkau
Post-DocsRalph Aβmann Mike SeidelPing Chou
VisitorsDr. Xiaoxi XuProf. Heino Henke
Accelerator Physics
Alex Chao - wakefields, spin-transport, beam instabilities, nonlinear dynamics, SLC, NLC, LHC
Tom Himel - accelerator controls, accelerator physics for colliders, SLC, PEPII
Roger Miller - microwave linear accelerators,rf structures, guns, SLC, NLCTA, NLC
Ron Ruth - nonlinear beam dynamics, linear colliders, NLCTA, NLC
Bob Siemann - beam measurements, diagnostics &instrumentation, high gradient accelerators, mm-waves, SLC
David Whittum - collective effects, beam interactions with microwaves, plasma, free-electron lasers, mm-waves, SLC
Perry Wilson - microwave linear accelerators, structures,pulse compression, mm-waves SLC, NLCTA, NLC
Courses in Beam Physics
Introduction to Accelerator Physics Bob SiemannLaboratory Electronics John Fox
Nonlinear Dynamics in Accelerators Alex Chao & David WhittumBeam Dynamics in Storage RingsAlex ChaoPhysics of Free Electron Lasers David Whittum
In addition, US & CERN Particle Accelerator Schools - seehttp://beam.slac.stanford.edu/
Electromagnetic Radiation from Relativistic ElectronsHelmut WiedemannAP 453A - 3 units - FallCollective Effects in AcceleratorsAlex ChaoAP 453B - 3 units - WinterMicrowave Linear AcceleratorsRoger Miller, Perry Wilson, David WhittumAP 453C - 3 units -Spring
Previous courses...
This year...
Courses This YearAP 453A: Electromagnetic Radiation from Relativistic ElectronsHelmut Wiedemann (Fall, 3 units)
The emission of electromagnetic radiation from relativistic electron beams is derived from first principles with special attention to coherent and incoherent synchrotron radiation, transition radiation, free electron lasers. This includes discussions of undulator and wiggler radiation with linear and elliptical polarization. The course is intended primarily for graduate students using such radiation for basic and applied research and students in accelerator physics concentrating on source developments and the study of particle beam characteristics and stability. Prerequisite: EM, Optics and special relativity is desirable.
AP 453B: Collective Effects in AcceleratorsAlex Chao, (Winter, 3 units)
An intense beam in an accelerator is subject to a variety of instability mechanisms. This course is a systematic introduction of these mechanisms, starting with Maxwell's equations. Topics of interest include wake fields, impedances, Landau damping, intra beam scattering, and the Vlasov equation. The instabilities studied include those for storage rings as well as linacs.
AP 453C: Microwave Linear AcceleratorsRoger Miller, David Whittum and Perry Wilson, (Spring, 3 units)
For students with a general interest in electron linear accelerators, in electron linacs for free electron lasers or in future linear colliders. Review of beam transport and emittance concepts; electron injection (guns, bunching and capture); accelerating structures; klystron theory and rf pulse compression; concepts of beam loading and wake potential; introduction to advanced particle acceleration, such as wake field and plasma accelerators.
Wakefield Instrumentation
LIGA
LIGA(in perspective)
End-S
tation B F
acility
VehicleAccess
PersonnelAccess
41'
50 TonCrane
WorkbenchesCable
Control
Storage-Racks
Cart/ForkliftAccess
EX1 -A
Electronics-Racks
PPSGate
17'
ESB Facility
Accelerator Research at the SLC
Linear Collider Beam DynamicsRalph Aβmann & Accelerator Dept.
Beam Dynamics of Damping RingsBoris Podobedov & Accelerator Dept.
Stanford Linear Collider
e- inject or
1.2 GeV e-damping for8.2 msec
1.2 GeVe+ damping for16.4 msec
SLD Detector
0.2 GeV e+accelerat or
33 GeV e- hittarget, make e+
e- e+
two-mile rf linac
Accelerator Physics at the SLC
e- e+
Inst abilit ies hereaffect bunch length,jit ter in the linac
St ruct ure misalignment shere increase thebeam emit tance
Bunch lengt h monit or(Ka Band)
St reak Camera(0.7 ps)
Bunch lengt h monit ors
ASSET Facilit y forwakefield st udies
(X-Band)
Mobile microwave labfor wakefield st udies
(C & Ku Band)
(st reak camera, CCD,gat ed CCD, spect rumanalyzer, Ku Band t o audio)
ARDB LAB
Main Cont rolCont rol Syst em
"SCP"
Other ProjectsBeam Dynamics in a mm-Wave LinacLaser-Wakefield 5 TeV Collider “Design”S-Band Structure Wakefield Studies at LI02 [Mike Seidel]
a)modelling b)bench measurements on a 10’ sectionc)hardware implementation d)commissioning
Sub-Micron Resolution Cavity BPM for Moller Scattering Experiment [Nicolo deGroot]
a)modelling b)prototype cavity fabricationc)cold-testing d)commissioning
Sub-Micron Resolution mm-Wave BPM for X-Ray Light Source [Bob Hettel, Fritz Caspers]
a)modelling b)prototype cavity fabrication & cold-testing c)commissioning
mm Bunch Length Monitor for Precision Z0 Studies [Jerry Yocky, Frank Zimmermann]
a)modelling b)hardware implementationb)commissioning
S-band Structure Dimpling for Precision Z0 Studies [Franz-Josef Decker, Pantaleo Raimondi]
a)theory of long range wakefields, effect of dimpling b)implementation on test stacksc)implementation on five sectors of the SLC d)commission on SLC
Studies of Field Emission on a Resonant Ring [Xiaoxi Xu]
a)modelling of a resonant ring b)implementation of ring diagnosticsmm-Wave Tube ("ubitron") [Klystron Dept.]
a)modelling b)engineering designc)fabrication d)commissioning
mm-wave Structure Design [Heino Henke, Norman Kroll] a)circuit analysis b)field calculationsc)wakefield analysis
What Has Changed?
●high-power, short-pulse,efficient lasers●phase,amplitude, jitter control of T3 lasers●channel guiding●microfabrication●wakefield instrumentation
New Results
New Directions (or Slightly-Used)
●PWFA Test at SLAC ●beam-combining●neutral beam collisions●matrixed linacs
Predictionsin the next year...
Can Do●CLIC will machine a DDS structure●PWFA at SLAC standying by for e-time●channel-guided LWFA results are in●NLC in engineering phase
Maybe Can Do●ultimate G in Cu known to 10%●field emission β understood, held to 20●30 MW W-Band tube being engineered●LWFA systems study in progress●beam combining, neutralization proposal●wakefields for 0.5mm bunch agree w/theory●AA Community particpates in SLC’s Last Run
For More Information on ARDB, Contact...
David Whittum, MS26 SLAC, Stanford University, 2575 Sand Hill Road, Menlo Park CA 94025 Tel: 415-926-2302 Fax: 415-926-4999Email:[email protected]: http://beam.slac.stanford.edu